Moderate drinking linked to lower diabetes risk

NEW YORK (Reuters Health) - Adults who have a drink or two per day may have a lower diabetes risk than teetotalers -- and the link does not appear to be explained by moderate drinkers' generally healthier lifestyle, a new study finds.

A number of studies have found an association between moderate drinking and a relatively lower risk of developing type 2 diabetes. However, whether that reflects a benefit of alcohol has been unclear. A central issue is the fact that, compared with both non-drinkers and heavy drinkers, moderate drinkers tend to have a generally healthier lifestyle.

In the new study, researchers found that among more than 35,000 Dutch adults followed for a decade, those who averaged a drink or two per day were 45 percent less likely than teetotalers to develop type 2 diabetes.

Moreover, the lower risk was seen among men and women whose diabetes risk was already relatively low because of their weight and lifestyle habits -- namely, not smoking, eating a healthy diet and getting regular exercise.

Even among study participants with at least three of those protective factors, moderate drinkers were 44 percent less likely than non-drinkers to develop type 2 diabetes.

The findings, reported in the American Journal of Clinical Nutrition, do not prove that drinking itself lowers diabetes risk. But they do suggest that the alcohol-diabetes connection is not explained away by other lifestyle factors.

"Our results indicate that this is very unlikely, because moderate drinkers with the most healthy lifestyle behaviors...had a lower chance of developing diabetes compared with subjects with these healthy lifestyle behaviors who did not drink," lead researcher Dr. Michel M. Joosten, of Wageningen University in the Netherlands and TNO Quality of Life in Zeist, the Netherlands, noted in an email to Reuters Health.

The findings are based on 35,625 adults who were between the ages of 20 and 70 and free of diabetes, heart disease and cancer at the outset. Participants had their weight, height and waist and hip circumference measured and completed questionnaires on their health and lifestyle habits.

Over the next 10 years, 796 developed type 2 diabetes.

In general, moderate drinkers -- up to a drink per day for women, and up to two for men -- were less likely to develop the disease than non-drinkers. And that remained true when Joosten and his colleagues examined the effects of other lifestyle-related factors.

For example, when they looked only at normal-weight men and women, moderate drinkers were 65 percent less likely to develop diabetes than teetotalers. Similarly, among regular exercisers, moderate drinkers had a 35 percent lower risk of diabetes.

The "take-home message," Joosten said, is that moderate drinking "can be part of a healthy lifestyle to lower your risk of type 2 diabetes, even if you already comply with multiple other low-risk lifestyle (behaviors)."

That said, he also noted that experts do not recommend that non-drinkers take up moderate drinking simply because it is related to lower risks of certain diseases. Alcohol always carries the potential for abuse, and the known risks of problem drinking have to be balanced against the possible health benefits of moderate drinking.

SOURCE: American Journal of Clinical Nutrition, online April 21, 2010.